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Outline of Topics • Taxonomy of reptiles and amphibians
• Key characteristics used to identify reptiles and amphibians
• The natural history and basic biology of reptiles and amphibians
• The diversity and distribution of reptiles and amphibians in Virginia
• Some common reptiles and amphibians occurring in the local ecosystems
• The role of reptiles and amphibians in Virginia ecosystems
Topics (Continued)
• The adaptations of reptiles and amphibians and how these relate to environmental factors
• The basic principles of reptile and amphibian management
• Threats and/or issues relating to reptiles and amphibians in Virginia
• Appropriate techniques and methods for studying reptiles and amphibians
• Rare or special species that indicate habitat qualities
Added Value
• Bibliographic Resources
• Web Resources
• Local Sites
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Number
Taxonomic Diversity of Virginia Herps
Families
Genera
Species
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Species
Geographical Species Density
Tidewater
Piedmont
Mountins
Taxonomy • Taxonomy – Nomenclatural system for
classifying evolutionary units.
– Latin binomials
• Class Amphibia
• Order Anura
• Family Hylidae
• Genus Pseudacris
• Species crucifer
–Genus always capitalized, species never
–Common name: Spring Peeper
Systematics • Systematics – The quest to develop a
classification that reflects the evolutionary history of lineages.
• Tools of the systemacist
– Morphology
– Development
– Genetics
– Phylogeny Reconstruction
– The Web http://tolweb.org/tree/
Phylogeny of the Extant Tetrapoda
Mammals Amniota Reptiles and Birds
Amphibia Frogs and Salamanders
Tetrapoda After: http://tolweb.org/Terrestrial_Vertebrates/14952
Evolved in the Devonian from lobe-finned fishes
Phylogeny of Living Amphibians
Salientia (Frogs and Toads)
Caudata (Salamanders and Newts)
Gymnophiona (Caecilians)
© 2005 Teague O'Mara Lissamphibia
Characteristics of Amphibians • Anura – Tailless jumping machine
–Nine or fewer presacral vertebrae
–Postsacral vertebrae fused as urostyle
–Radius and ulna fused as radioulna
– Tibia and fibula fused as tibiofibula
• Caudata
– Tail in larva, juveniles, and adults
– Two pairs of limbs
–Many technical skeletal characters
Frogs Families of Virginia
• Scaphiopidae – Spadefoot Toad
• Bufonidae - American Toad
• Microhylidae – Narrow-mouthed Toad
• Hylidae – Spring Peeper
• “Ranidae” - Bullfrog
The Anuran Life Cycle
Egg
Larva (Tadpole)
Juvenile
Adult
Anuran Larvae • Filter-feeders
• Rasping mouthparts
• Coiled intestine
Role of Anurans in Aquatic Food-webs
Tadpoles
Periphyton Phytoplankton
Fish Salamanders Snakes Insects Birds
Role of Anurans in Terrestrial Foodwebs
• Juvenile and Adult Frogs Eat Insects
–Adult Bullfrogs eat Crayfish and Smaller frogs
• Juvenile and Adult Frogs Are Eaten By Many mesopredators
–Mammals: Raccoons, skunks, mink, etc.
– Snakes: Gartersnakes, watersnakes, etc.
–Birds: Herons, hawks, grebes, etc.
Species of Frogs in Albemarle County
• Toads
–American Toad
–Fowler’s Toad
• Tree Frogs
–Upland Chorus Frog
–Spring Peeper
–Grey Treefrog
True Frogs of Albemarle County
• True Frogs
–Bullfrog
–Green Frog
–Leopard Frog
–Pickerel Frog
–Wood Frog
Optimal Timing of Metamorphosis
The balance between growth opportunities and mortality risk
Grey Tree Frog
Flash Colors
Turbo Tadpoles
Range of Gray Treefrog
Range of Woodfrog
Salamander Families of Virginia
• Sirenidae: Siren
• Cryptobranchidae: Hellbender
• Necturidae: Necturus (mudpuppy)
• Salamandridae: Newts
• Ambystomatidae: Mole salamanders
• Amphiumidae: Amphiuma (Conger eel)
• Plethodontidae: Woodland salamanders
Salamander Life Cycles
• Primitive Condition: Aquatic Egg →
Aquatic Larva → Terrestrial Juvenile → Terrestrial Adult
• Direct Development: Female lays a clutch
of a few large eggs in a terrestrial site where she attends them. The larval stage and metamorphosis are completed within the egg capsule.
Salamanders of Albemarle County
• Salamandridae
–Red-spotted Newt
• Ambystomatidae
–Marbled Salamander
–Spotted Salamander
• Plethodontidae - lungless
Plethodontids of Albemarle County
• Plethodontidae
– Red-backed Salamander
– Slimy Salamander
– Two-lined Salamander
– Northern Dusky Salamander
– Seal Salamander
– Mud Salamander
– Red Salamander
– Spring Salamander
Red-spotted Newt
Egg
Larva Paedo-morph
Eft Adult
Adult
Marbled Salamander Life Cycle
• Adults move to dried pond basins in early fall
• Courtship is on land in September
• Females lay eggs and attend them in fall
• Pond floods with autumnal rains
• Larvae hatch when flooded
• Larvae winter in pond
• Larvae metamorphose and leave pond in June
Spotted Salamander Eggs
Spotted Salamander Life Cycle
• Males move to ponds soon after ice leaves
• Females move to pond early spring rain
• Courtship and egg deposition in water
• Males and females leave following rain
• Eggs hatch late spring
• Larvae metamorphose and leave pond in mid summer
Tiger Salamanders are Endangered in Virginia and other states on the East Coast
Red-backed Salamander
Plethodon cinereus complex
• P. shenandoah – Stony Man, Hawksbill, The Pinnacles of SNP.
• P. hubricti – Peaks of Otter
• P. nettingi – Cheat Mountain, WV
• P. cinereus – widespread in surrounding habitats
Eggs of the Two-lined Salamander
Embryos of the Two-lined Salamander
Amphibian Conservation Biology • Threats
–Habitat Loss (breeding sites, foraging areas)
–Pollution (pesticides)
–Disease (chytrid fungus, ranovirus)
–Predation (fish, feral cats)
• Remediation
–Wetland restoration
–Cover habitats
– Fish removal
Natural Populations
Methods to Study Amphibians:Experimental Populations
Extant Groups of Amniotes
• Birds and Crocodylians
• Turtles and Tortoises
• Squamates (Lizards and Snakes)
• Tuatara
• Mammals
Phylogeny of the Amniotes:The Terrestrial Vertebrates
Synapsida (Mammals)
Anapsida: Testudines (Turtles)
Romeriida: Diapsida Birds, Lizards, Snakes
http://tolweb.org/Amniota/14990
The Amniotic Egg
Turtles of Virginia • Chelydridae
– Snapping Turtle
• Kinosternidae
– Mud Turtle
– Stinkpot
• Emyidae
– Painted Turtle
– Eastern Box Turtle copyright © E. S. Gaffney
Temperature-Dependent Sex Determination
Painted Turtle in Nebraska
The sex of many turtles, lizards, snakes, and alligators is determined by temperature during a critical period of development in the nest.
Conservation Biology of Turtles
• Threats
– Habitat Destruction (wetlands and nesting sites)
– Highways
– Pollution by pesticides
– Climate Change?
• Remediation
– Natural areas
– Education
Phylogeny of the Diapsida
Sauria
Archosauromorpha (Crocodilians and Birds)
Lepidosouromorpha (Lizards, Snakes, Tuatara)
http://tolweb.org/Diapsida/14866
Diapsids have a large suborbital fenestra
Dinosaurs
Lizards of Albemarle County • Teiidae
– Six-lined Racerunner
• Phrynosomatidae
– Eastern Fence Swift
• Scincidae
– Five-lined Skink
– Broad-Headed Skink
Range of Broad-headed Skink
Conservation Biology of Lizards
• Threats
– Habitat Destruction
– Feral Cats
– Pesticides
• Remediation
– Natural Areas
Poisonous Snakes of Albemarle County
• Crotalidae
– Copperhead
– Timber Rattlesnake
Geographic Range of Cottonmouth
Range of Northern Watersnake
First Aid for Snakebite
• Stay calm
• Treat for Shock
• Elevate bitten limb
• Get Patient to a Hospital for Antivenin
Nonpoisonous Snakes of Albemarle • Colubridae
– Black Ratsnake
– Black Racer
– Corn Snake
– Milk Snake
• Dipsadidae
– Wormsnake
– Ring-necked Snake
• Natricidae
– Ribbon Snake
– Garter Snake
– Northern Watersnake
Hog-nosed Snake
Hog-nosed Snake
“Dead” Hog-nosed Snake
Conservation Biology of Snakes
• Threats
– Habitat Destruction
– Human Ignorance
• Remediation
– Natural Areas
– Education
Educational Resources
• Bibliographic
• Web
– Tree of Life Project http://tolweb.org/tree/
– http://www.ucmp.berkeley.edu/taxa/verts/diapsida.php
– http://www.cnah.org/
• Local Experts (UVa Biology)
– Butch Brodie
– Bob Cox
Find More Information www.dgif.state.va.us/
Books worth having
• Atlas of Amphibians and Reptiles in Virginia by Joseph C. Mitchell and Karen K. Reay
• The Reptiles of Virginia by Joseph C. Mitchell
• Peterson’s Field Guide to Reptiles and Amphibians by Robert Powell and Roger Conant 2016.
• Books on each group by Whit Gibbons
